Generally, illuminated fabric displays (hereinafter, referred simply as to “IFD”) are defined as communicating textiles that are well known to display information (character, figure, sign, graph, and so forth) on fabrics as fabric base communicational media for information. Electroluminescent materials, electron element, and sensors are printed on fabrics, so that they radiate light by itself. Data transmitted by light are displayed variously via wireless distant control system. These IFD are distinguished from flexible display or e-paper formed by substituting glass substrates with polymer substrates. It is expected that IFD will be the basis of next generation display.
Until now, fabric-base display technique employs optical fibers inserted into fabrics while weaving, light emitting diode (LED) inserted into conductive textile array, and electroluminescence materials arranged on fabrics.
For instance, luminex developed by luminex company located in Italy means clothes irradiates light by weaving plastic optic fiber. By employing etching techniques, light is emitted. In addition, when optic fibers are weaved, light of LED is emitted conformally via curved portions thereof. Bill-Blanket LightMat manufactured by lumitex company is a fabric using such technique. Meanwhile, plastic optical fibers (POF) as signal transmitting fibers have been introduced, but are not disclosed in various applications. Also, lumalive by Philips develops illuminated materials capable of displaying stop image as well as animation by combining flexible LED device and a control unit on the back of fabrics, but this lumalive can be manufactured by mounting LED on mesh fabrics. Lumimove by Crosslink company is illuminated materials by adopting electroluminescent materials emitting light using electric field and applied in military tents and so forth.
Korea Patent Gazette teaches a flexible inorganic EL comprising: a substrate composed of polymer synthetic rubber, polyurethane, and silicone rubber; a bus bar composed of high-conductivity paste and a binder; a transparent electrode layer composed at least one selected from the group consisting of ITO paste composed of Indium Tin Oxide (ITO) and a binder, Antimony Tin Oxide (ATO), and conductive polymer, or a mixture of conductive polymer and the ITO paste; a fluorescent layer composed of a mixture of fluorescent paste (ZnS) and high-k dielectric constant binder; a dielectric layer composed of a mixture of a dielectric paste and a binder; a conductive layer composed of at least one selected from the group consisting of a mixture of a conductive paste and a binder, conductive organic polymer, and a mixture of conductive paste and organic polymer; and a polymer protecting layer composed of at least one selected from the group consisting of fluoride-based polymer, a binder including polyurethane, and IR or UV curable polymer. A polymer layer having the same material as the polymer protecting layer may be interposed between the substrate and the bus bar. A polymer insulating layer having the same material as the polymer protecting layer may be interposed between the conductive layer and the polymer protecting layer. A second conductive layer having the same material as the conductive layer may be interposed between the conductive layer and the polymer protecting layer.
Additionally, Korea Patent Gazette teaches a two sides light-emitting EL device comprising: a first transparent electrode layer (transparent electrode layer having several nm thickness stacked by sputtering transparent electrode material (e.,g, ITO) disposed on a transparent insulating substrate composed of transparent insulating material (e.,g, PET film); a first EL device comprised of a first fluorescent layer, a first insulating layer, and a back electrode layer (opaque electrode material), which are stacked sequentially; a second EL device disposed on the first EL device and comprised of the back electrode layer used as a common electrode, a second insulating layer, a second fluorescent layer, and a second transparent layer formed by printing technique using paste including transparent electrode material), which are stacked sequentially; and a transparent protecting layer for protecting upper portions and sidewalls of the first and second EL devices, wherein the transparent electrode layer is formed by a printing technique using ink made of polyester material or film to be laminated. The first and second transparent electrode layers are connected to a first output terminal in parallel of a driving circuit. The back electrode layer is connected to a second output terminal. The first electrode layer, the back electrode layer, and the second transparent layer are connected to the first output terminal, the second output terminal, and a third output terminal of the driving circuit, respectively.
While EL devices of the above-mentioned patents may be feasible when applied to PET films, polymer synthetic rubbers, polyurethane, or silicone rubbers, they may present additional difficulties and inherent limitations of their application on fabrics.
There are the limitations that it is difficult for a illuminated fabric display to be capable of achieving high luminance with respect to single or multi color information such as character, figure, sign, graph, and so forth as well as having excellent flex resistance, wash resistance, wear resistance, durability, flexibility, drape, electrical stability, 3D function.
Moreover, a conventional illuminated fabric display employing a substrate composed of optical fiber, polymer synthetic rubber, polyurethane, or silicone rubber has characteristics of low elasticity and softness. Even if it has elasticity and softness, it is not enough to be applied in industry due to the limited use thereof.